Use correct section flags (causes a page fault)

src/memory/paging/entry.rs

@@ -8,6 +8,7 @@
 // except according to those terms.
 
 use memory::Frame;
+use multiboot2::ElfSection;
 
 pub struct Entry(u64);
 
@@ -52,3 +53,24 @@ bitflags! {
         const NO_EXECUTE =      1 << 63,
     }
 }
+
+impl EntryFlags {
+    pub fn from_elf_section_flags(section: &ElfSection) -> EntryFlags {
+        use multiboot2::{ELF_SECTION_ALLOCATED, ELF_SECTION_WRITABLE, ELF_SECTION_EXECUTABLE};
+
+        let mut flags = EntryFlags::empty();
+
+        if section.flags().contains(ELF_SECTION_ALLOCATED) {
+            // section is loaded to memory
+            flags = flags | PRESENT;
+        }
+        if section.flags().contains(ELF_SECTION_WRITABLE) {
+            flags = flags | WRITABLE;
+        }
+        if !section.flags().contains(ELF_SECTION_EXECUTABLE) {
+            flags = flags | NO_EXECUTE;
+        }
+
+        flags
+    }
+}

src/memory/paging/mod.rs

@@ -204,7 +204,7 @@ pub fn remap_the_kernel<A>(allocator: &mut A, boot_info: &BootInformation)
                      section.addr,
                      section.size);
 
-            let flags = WRITABLE; // TODO use real section flags
+            let flags = EntryFlags::from_elf_section_flags(section);
 
             let range = Range {
                 start: section.addr as usize,